exam 3 review

Question 1

what is metabolism

Answer 1

the entire set of enzyme-catalyzed transformations of organic molecules in living cells; the sum of anabolism and catabolism

Question 2

what is anabolism

Answer 2

the phase of metabolism concerned with the energy-requiring biosynthesis of cell components from smaller precursors

Question 3

what is catabolism

Answer 3

the phase of metabolism concerned with the energy-yielding degradation of nutrient molecules.

Question 4

where does glycolysis occur

Answer 4

in the cytoplasm

Question 5

where does pyruvate oxidation, and the citirc acid cycle occur

Answer 5

in the mitochondrial matrix

Question 6

where does electron transport and ATP synthesis (creation of CO2 and H2O as well) occur

Answer 6

in the inner mitochondrial membrane

Question 7

in the overall reactions of glycolysis, what do we start with?

Answer 7

1 glucose, 2 NAD+, 2 ADP, 2Pi

Question 8

in the overall reactions of glycolysis, what do we end with?

Answer 8

2 pyruvate, 2 NADH, 2 ATP, 2 H20, 2H+

Question 9

Can NAD+ be transferred to the electron transport chain?

Answer 9

yes, 4 electrons are passed to NAD+ which when it becomes NADH make it transferrable.

Question 10

step 1 of glycolysis

Answer 10

Glucose is phophorylated with a kinase mkaing glucose 6-phosphate; taking energy from ATP and transferring it to glucose.

Question 11

step 2 of glycolysis

Answer 11

An isomerase swaps the oxygen and hydroxyl groups to rearrange the molecule.

Question 12

step 3 of glycolysis

Answer 12

phosphorylation of fructose-6 phosphate catalyzed by phosphofructokinase. an ATP donates a phosphate group producing fructose-1, 6-bisphosphate and ADP as products

Question 13

step 4 of glycolysis

Answer 13

Lysis of glycolysis where an enzyme is enacted to split the sugar into 2 3-carbom molecules each with a phosphate group

Question 14

step 5 of glycolysis

Answer 14

triosephosphate isomerase interconverts he molecules dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP) removing glyceraldehyde completely

Question 15

step 6 of glycolysis

Answer 15

2 seperate rxns occur:
1. glyceraldehyde-3-phosphate is oxidized by the coenzyme (NAD)
2. the molecule is phosphorylated by the addition of a free phosphate group.

Question 16

step 7 of glycolysis

Answer 16

we see payoff with the production of 2 ATP. Phosphoglycerate kinase transfers a phosphate group from 1,3-bisphosphoglycerate to ADP to form ATP and 3-phosphoglycerate.

Question 17

step 8 of glycolysis

Answer 17

The enzyme phosphoglycero mutase relocates the P from 3- phosphoglycerate from the 3rd carbon to the 2nd carbon to form 2-phosphoglycerate. rearrangement of phophate groups.

Question 18

step 9 of glycolysis

Answer 18

The enzyme enolase removes a molecule of water from 2-phosphoglycerate to form phosphoenolpyruvic acid (PEP). Enolase works by removing a water group, or dehydrating the 2 phosphoglycerate.

Question 19

step 10 of glycolysis

Answer 19

The enzyme pyruvate kinase transfers a Phosphate from phosphoenolpyruvate (PEP) to ADP to form pyruvic acid and ATP Result in step 10.

Question 20

Which steps of glycolysis have large -∆ G and what does that mean?

Answer 20

Steps 1, 3, and 10 have large -∆ G’s meaning that these steps are essentially irreversible.

Question 21

what step of glycolysis is oxidation?

Answer 21

step 6, coenzyme NAD+ turns into NADH

Question 22

which two steps of glycolysis have substrate level phosphorylation?

Answer 22

Steps 7 and 10 where the first and second ATP forming reactions occur

Question 23

what are the pathways pyruvate (product of glycolysis) can take?

Answer 23

1. can be completely oxidized into 2 CO2 aerobically and generate more ATP
2. can be processed anaerobically to lactate or ethanol